Single Wire Output Logger (SWOL) Users Guide

Table of Contents

Single Wire Output Logger (SWOL)

SWOL is an ecosystem to provide extensive, flexible, yet minimally invasive debug information using the ARM ITM module on Texas Instruments (TI) CC13x2 / CC26xx devices. The debug information is then parsed with Python and outputted / viewed using Wireshark.

Overview

The ecosystem consists of the following parts, which are expanded upon in sections below:

• SWO Driver: An embedded driver to send various debug output (formatted text, data dumps, etc) through a single-wire serial interface. For documentation on this, see the Doxygen only after completing the Quick-Start demo here
• Logger: Python code to parse .elf file, receive and parse seral data, build into high-level frames, and send to Wireshark. For documentation on this, see TODO
• A basic Wireshark dissector to display frames and timing in Wireshark
• Gandelf: A GUI configuration tool (Gandelf) provided as an executable to set input files, settings, and manage the pipe between Python and Wireshark.

Environment Setup

These instructions will detail how to get a SWOL Test project running on your local machine for development and testing purposes.

Currently, this has only been tested on Windows 10. It theoretically should work on all operating systems but you are on your own to verify this. There are most likely bugs. Testing for other operating systems is planned for future work.

Hardware Prerequisites

• A development board that includes XDS-110 such as the CC26X2R Launchpad. Ensure that the SWO jumper is attached:

Software Prerequisites

• A TI Software Development Kit (SDK) for the appropriate hardware. Supported versions are:
  • SimpleLink™ CC13x2 and CC26x2 software development kit (>= v3.20.00.xx)
  • SimpleLink™ CC2640R2 SDK (>= v3.20.00.xx)
• An IDE (Code Composer Studio or IAR) as stated in the release_notes_xxx.html file included at the top directory of the above SDK
• Wireshark (>= 3.0.2)

Installing

This assumes that the above prerequisites are already installed.

1. The SWOL plugin is not currently provided as an installer. Therefore, it is necessary to copy the entire swol_x_xx_xx_xx directory into C:/ti. Do this first. This location will henceforth be referred to as $SWO_PLUGIN_INSTALL$
2. Add the SWOL dissector to the Wireshark plugins directory.
   1. Find the plugins directory specific to the Wireshark installation. In Wireshark, goto Help->About Wireshark and select the Folders tab. Take note of the “Global Plugins” folder
   2. Copy the swol_tools/swo_logger_tools/logger/dissector/wireshark_dissectors/swol_dissector.lua file into the “Global Plugins” folder from the previous step

Quick-Start Logging Demo

The plugin comes with a swo_test embedded project that demonstrates all possible SWO commands and some module parsing. Run this demo first to verify that the environment is setup correctly. To run this demo:

1. Compile and download the swo_test project. See below for IDE-specific instructions
   • CCS:
     1. Open the project in CCS from $SWO_PLUGIN_INSTALL$/examples/rtos/ in the appropriate board folder
     2. Install the SWO plugin. Go to Window->Preferences->Code Composer Studio->Products and add $SWO_PLUGIN_INSTALL$ to the “Product Discovery Paths”
     3. Compile and download the project
   • IAR:
     1. Set the global argvars. Go to Tools->Configure Custom Argument Variables and import, as a global argvar, $SWO_PLUGIN_INSTALL$/tools/iar/swol_xxxx.custom_argvars for the appropriate board.
     2. Open the project in IAR from $SWO_PLUGIN_INSTALL$/examples/rtos/ in the appropriate board folder
     3. Compile and download the project
2. Run $SWO_PLUGIN_INSTALL$/tools/gandelf/gandelf.exe to open the configuration tool
3. Set the path to the top-level Wireshark directory.

4. Click the icon to add a logger, choose SWO, and configure, pointing to the appropriate files and ports:

   

   These options are the parameters that are passed into logger.exe. So for more information on any option, run the following from your terminal of choice:

   logger.exe -h

5. Click start. This will open Wireshark, start the logger, and create a pipe between the two.

6. Once the Wireshark output says “Connected to COMXX”, reset the device to start logging. The output should look something like this:

   

Using SWOL

Using Pre-existing Modules

Now that the demo is running, and thus the environment setup has been verified, SWOL can be added to an existing project. All of the necessary information to accomplish this can be found in the “Usage” section of the SWO.h API Documentation

Adding a Custom Module

TODO

Using Python Source Logger

By default, Gandelf is configured to use a pre-compiled Logger executable. This is sufficient if it is only desired to use the built-in Logger modules. If it is desired to create a custom Logger module or modify the Logger in any way, it is required to use the Python source code. This adds the following software requirements:

• Python (>= 3.7.x)

To use the python source code instead of the executable, perform the following.

1. Install python requirements:

   pip install -r $SWO_PLUGIN_INSTALL$/tools/logger/pip-requirements.txt

2. Instruct Gandelf to call logger.py instead of the executable. This is done by setting the SWO “binary” in $SWOL_PLUGIN_INSTALL$/tools/gandelf/loggers/loggers.json to point to the executable. Here is an example for Windows:

   {
       "id": "swo",
       "project": "SWO",
       "name": "SimpleLink SWO",
       "icon": "loggers/swo/swo.svg",
       "binary": "../logger/logger.py",
   },

   Note that Gandelf will need to be restarted for this change to take effect.